Prevention-PMTCT: Women who start ART in pregnancy do just as well as non-pregnant women
HIV-infected women who start antiretroviral treatment during pregnancy have similar or better immunological outcomes in the first two and a half years on treatment as non-pregnant women as well as men in the MTCT-Plus Initiative covering seven countries in sub-Saharan Africa and Thailand from 2003-2006 reported Patricia Toro and colleagues in the journal AIDS.
The authors also noted lower mortality rates as well as high retention in care for all patients starting antiretroviral treatment when compared to other multi-site studies in similar settings.
These findings lend further support to the recently revised World Health Organization (WHO) guidelines prioritising the identification and treatment of HIV-infected pregnant women for their own health as well as that of their infants.
Decreases in morbidity and mortality are well-documented outcomes of the continued success of the rollout of antiretroviral treatment in resource-poor settings.
However when compared to resource-rich settings there is evidence of high early mortality because treatment is started at an advanced stage of illness. This means getting people onto treatment earlier and keeping them in care are essential if morbidity and mortality rates are to improve.
While ART scale-up has progressed, prevention of mother-to-child transmission (PMTCT) programmes are not keeping pace. An estimated 30% of pregnant women received ART for PMTCT in 2008, with the majority getting single dose nevirapine (SD-NVP), the least effective form of treatment.
Only 13% of HIV-positive pregnant women in antenatal care were assessed for ART for their own health in 2008.
Most women of reproductive age in resource-limited settings are identified as HIV-infected within the context of PMTCT, usually at an advanced stage of illness, putting them at increased risk of death as well as presenting a greater risk of transmission to their infants.
There is little evidence on the long-term outcomes of pregnant HIV-positive women who start antiretroviral treatment during pregnancy in resource-poor settings. Retention in care for mother and child is critical. Pregnancy is considered a risk factor for loss to follow-up.
The MTCT-Plus Initiative provides support to clinical programmes in Cameroon, Côte d’Ivoire, Kenya, Mozambique, Rwanda, South Africa, Uganda, Zambia and Thailand to provide HIV/AIDS care and treatment to families identified through perinatal HIV prevention services.
Pregnant or women who had recently given birth (index women) identified as HIV-infected in PMTCT programmes were invited to enrol in the initiative which offered comprehensive care and ART. Family and household members of HIV-infected women were also eligible for enrolment.
Of a total of 6421 adults enrolled in the Initiative from 2003-2006, 2229 were ART-naïve and were included in the analysis. 1688 (76%) were women, of which 605 (36%) were pregnant at the start of ART (median gestational age 7 months, interquartile range (IQR 6-8)).
The non-pregnant women began ART at a median time of 11 months after having given birth IQR 5-23. 541(24%) were male partners.
At 30 months on ART the average CD4 cell count was 451 cells/mm3 (baseline 147 cells/ml) in pregnant women compared to 435 cells/ mm3 among non pregnant women and 349 cells/ mm3 among men. These findings are similar to other multi-site studies in resource-poor settings and suggest that immunological response during pregnancy is similar to that in non-pregnant women and adult males.
The authors noted that median baseline CD4 cell count in their cohort was significantly higher than in other studies in similar settings, probably because of the specific nature of their programme to enrol pregnant as well as postpartum HIV-positive women and their partners.
Women who previously received sd-NVP for PMTCT were included as treatment naive in the analysis. Studies have shown that when treatment with a non nucleoside reverse transcriptase (NNRTI)-based regimen is started with a substantial delay after SD-NVP, as in this study (median of 11 months), immunological and clinical outcomes are not adversely affected.
While all sites used the same treatment protocols, the CD4 cell response rate had a direct relation to country of enrolment. The authors suggest that factors including resources, human and financial, at individual sites, as well as biological differences such as viral subtype and underlying opportunistic infections may have influenced the CD4 cell response rate.
After 30 months on ART retention rates were high and similar among all adults: 82% for pregnant women, 86% for men and 87% for non-pregnant women.
The authors suggest that the MTCT-Plus model of care in which psychosocial support and adherence to care and treatment are emphasised contribute to lower mortality risk as well as high retention rates. In addition all sites have high provider-patient ratios, as well as access to a wide range of supportive services.
Strengths noted by the authors include:
- All sites followed standardised MTCT-Plus protocols, received standardised MTCT-Plus training and used standardised data collection forms.
- Most of the patients began an NNRTI-based regimen primarily with nevirapine resulting in a fairly uniform treatment population.
And, limitations noted by the authors include:
- Data came from a clinical care programme rather than a research study and accounted for the probability of variations of CD4 cell counts across programmes as measurements were done in local laboratories
- Analysis of data was limited to those with baseline CD4 cell counts and at least one follow-up. This resulted in those at highest risk for poor outcomes being excluded, either because of early death or not being able to return for follow-up. While those excluded did not differ significantly in terms of CD4 cell count or gender, pregnancy status, age, education, employment, housing conditions or WHO stage from those included in the analysis, they were included in the analysis of retention rates.
The authors conclude “HIV-infected women in resource-limited countries who start ART during pregnancy have similar or better long-term CD4 cell count responses as compared with other adults. These data support efforts to provide pregnant HIV-infected women with access to ART in resource-limited countries.”
Toro PL et al. Initiation of antiretroviral therapy among pregnant women in resource-limited countries: CD4+cell count response and program retention. AIDS, advance online publication, December 7, 2009.